The broad long term objectives of this proposal are to: A)Determine accurate rate constants for elementary hydrocarbon reactions that contribute to the production of ozone. B) Teach students how to perform basic scientific research with state of the art equipment. C) Provide fundamental mechanistic information about how anthropogenic and biogenic hydrocarbons enhance ozone production in urban areas. This type of fundamental information is needed for modelers and atmospheric scientist to make accurate predictions of future ozone levels and the environmental impact of these levels on human health in urban areas. The specific aims of the proposal are A) to study the chemical kinetics of alkene and aromatic species produced naturally and by man that increase ozone production and thus affect human health and the environment. B) to publish these results in scientific journals as well as present at meetings, to make the information available to the general scientific community. Students will participate in preparing posters and drafting manuscripts as well as presenting the results at scientific meetings.